Hey guys. I have a 08 F250 v10 4x4 that only has 38k miles. im the second owner and i failry sure that the truck was never put in 4x4. i have noticed that dust seal on the front axle is out (and has been for a while). I think that may have caused a bearing in the front hubs to go out? now i get a knocking noise when in 4x4 the noise is not constant but does the knock when i hit the gas. it also knocks/bangs when in 2 wheel drive and turning hard. Could it be the u joints on the front ends or is it the wheel bearings? any help would be nice.

 

Manual or automatic hubs? If they are manual, have the hubs been locked a lot? If so it could be the axle u-joints. I'd also stick my head underneath and give the front drive shaft a wiggle - I've seen the u-joints there go bad. That shouldn't happen if the 4x4 isn't used, but it's easy to check.

I doubt that the hubs are bad, unless you are running big tires. That dust seal doesn't really do too much.

 

They are manual hubs. I dont know if the first owner left them locked in. i got the truck with 24k on it and it has the orginal size tires. i did slide under and i could wiggle the shafts fairly easy. it didnt look/feel like the u joints we moving but more like the shafts are moving, which is why i thought i had some bad bearings.

 

The axles will wiggle a surprising amount when the hubs are unlocked - there isn't too much supporting them. Unless the u-joints are really shot, you have to look pretty closely to see if there is any play in the u-joint itself. Mine were on the way out (bad knocking around the corners with the hubs locked), but I couldn't see any play in them.

If you have 4x4 off, and the hubs unlocked, can you turn the front axle by hand (just to make sure everything is disengaging the way it should)? Assuming it moves freely, is there still the knocking while cornering? If there is, it'll be something other than the axle/drive shaft.

Maybe the little needle bearings inside the hub? I'd still be surprised if the hub itself was bad, but I suppose it's possible too.

 

well i checked to see if the axles would spin free with the hubs unlocked....and they didnt move. i had to lock and then unlock the hubs for them to spin. so. i bet that most of the time they have been lock in for most of the 38k miles. i hope that i can replace just the spindle bearing and fix the knocking issue and save the money on the u joints.

 

I have a 2004 4x4 with the auto hubs. I recently had to have the truck towed on roll back flatbed due to head gasket failure. Strange is ever since I got the truck back when I make a left turn under power not as much coasting or breaking , I hear and fell a bumping noise. I have jacked up front end and wiggled front wheels to see if it may be wheel bearing? But no play or wiggle. My axle shafts a free and spin fine so my hubs are not engaging unless when I only turn left?
Again this is only when I turn left under power not coasting as much or applying breaks.